If you really want to keep it simple; just names and phone numbers.
Tested with APDE Kitkat 4.4 and Lollipop 5.1 using permission
READ_CONTACTS
You know how to place Android buttons?
If not see templates on my repo here.

Here is how to send a msg.
I, unfortunately, could not test it because I get the warning “You have no credits.”
If you have some time please cheque my templates on repo for errors.
Needs permission SEND_SMS